Am'jSyr'i9i4arm'}    Chemistry  of  Pressor  Compounds.  301 
acid-alcohol  precipitate,  or  from  the  acetic  acid  extract  of  the  glands, 
but  as  yet  we  have  been  unable  to  obtain  an  active  pressor  compound 
from  any  of  these  precipitates.  Aldrich  claims  to  have  obtained  an 
active  crystalline  picrate  by  precipitation  with  picric  acid  from  a 
concentrated  solution  of  the  glands  purified  by  precipitation  with 
uranium  acetate,  but  he  has  published  no  analyses  of  this  picrate. 
We  found  that  sodium  tungstate  gave  an  active  precipitate  which 
was  soluble  in  acetic  acid,  but  a  control  solution  of  sodium  tung- 
state also  caused  a  rise,  hence  we  cannot  say  whether  or  not  the 
activity  was  due  to  the  reagent.  We  have  been  unable  to  throw  out 
an  active  base  by  means  of  alkalies,  or  any  active  combination  of 
it  by  means  of  aluminum  hydroxide,  but  obtained  an  amine  odor  on 
treatment  of  active  solutions  with  an  alkali.  Magnesium  oxide 
seemed  to  carry  down  mechanically  some  of  the  pressor  compound. 
No  active  volatile  compound  was  obtained  by  alkaline  distillation. 
A  marked  odor  of  skatol  arose  on  treating  Pituitrin  with  hydro- 
gen peroxide,  and  the  solution  lost  its  pressor  action.  Schaefer  and 
Herring  state  that  extracts  of  the  pituitary  glands,  when  treated 
with  this  reagent,  still  induced  an  increased  urinary  secretion,  but 
produced  merely  a  slight  rise  in  blood-pressure.  In  their  experi- 
ments reducing  agents,  such  as  zinc  and  hydrochloric  acid,  were 
without  effect,  either  on  the  diuretic  or  on  the  pressor  action  of  such 
preparations. 
Recently  Baudouin  41  claims  that  he  has  obtained  an  ash- free, 
hygroscopic  compound  by  dissolving  the  dried  acetic  acid  extract  in 
absolute  ethyl  alcohol  and  freezing  out  the  active  substance.  From 
methyl  alcohol  solution  of  the  acetic  acid  extract  we  succeeded  in 
freezing  out,  by  means  of  solid  carbon  dioxide,  an  almost  white 
precipitate  which  caused  a  marked  rise  in  blood-pressure,  and  the 
filtrate  was  only  slightly  active,  but  on  resolution  of  this  active  pre- 
cipitate, freezing  gave  no  precipitate. 
After  precipitating  with  lead  subacetate  and  removing  as  much 
of  the  lead  as  possible  by  phosphoric  or  sulphuric  acid  the  filtrate 
was  still  active,  even  though  hydfogen  sulphide  was  used  to  remove 
the  last?  traces  of  lead ;  but  if  hydrogen  sulphide  alone  was  used  to 
remove  the  lead,  both  the  filtrate  and  precipitate  became  inactive, 
but  solutions  of  the  glands  to  which  lead  had  not  been  added  were 
41  Baudouin,  A.,  "  Sur  le  recherche  du  principe  actif  de  l'hypophyse," 
Comp.  rend.  Soc.  de  Biol,  vol.  74,  p.  1138  (1913). 
